The present invention relates to an information storage medium, a synchronization control method and a computer terminal.
An online game that allows a plurality of players to participate in and play a game through a network has been known. In such an online game, a game device exchanges data with another game device through a network, and proceeds with the game in synchronization with the other game device. For example, JP-A-2001-17735, JP-A-2002-186785, and JP-A-2005-6913 disclose technology that proceeds with a game while achieving synchronization between game devices.
Since a communication delay occurs when exchanging data through a network, it is necessary to reflect the operation input of the player in the game while taking account of the communication delay. However, since the communication environment of the player who participates in the online game varies according to time and circumstances, a long period of time may be required until the operation input of the player is reflected in the game, if the operation input of the player is reflected in the game on the assumption that the communication delay is constant. In particular, when implementing a game in which the operation input timing of the player is important (e.g., fighting game), the player cannot fully enjoy the game if the response to the operation input of the player is delayed.
JP-A-2006-32502 discloses a method that implements a quick-response game by predicting the movement of another player's character operated by another player based on the communication delay time of data received from another game device so that the player's character and the other player's character maintain consistency. However, a method that predicts the movement of another character is not suitable for a game in which the operation timing is important (e.g., fighting game). For example, when executing a fighting game, game calculations are sequentially performed when input information has been input by each player so that each character makes a motion. Therefore, it is difficult to employ a method that predicts the motion of each character.